methodology for environmental profiles 2008 sd6050

8/12/2019 Methodology for Environmental Profiles 2008 SD6050

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SD6050 Issue 1.0 BRE Global Environmental Profiles methodology 2008 5

Uncontrolled copy if printed. Valid on day of printing only. BRE Global Ltd 2008

Acknowledgement

The Environmental Profiles methodology was first published in 1999. This 2009 update has been madepossible with the kind support of:

BRE Trust

Department for Children, Schools and Families (DCSF)

Department for Business Enterprise and Regulatory Reform (BERR)

Energy Savings Trust (EST)

English Partnerships (now Homes and Communities Agency)

Housing Corporation (now Homes and Communities Agency) HSBC

National House Building Council (NHBC)

Office of Government Commerce (OGC)

Oxford Brookes University

Post Office (Royal Mail)

RBS

Waste and Resources Action Programme (WRAP)

Willmott Dixon

and the contribution of the Construction Products Association and its members.


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Peer review statement

The following experts in LCA and buildings have undertaken a peer review of this methodology:

Wayne Trusty, Athena Sustainable Materials Institute, Canada (Chair)

John Bowdidge, Independent LCA expert, UK

Eva Schmincke, Five Winds Consultancy, Germany

The peer review team congratulates BRE Global on the production of a well-researched and well-developed PCR methodology. The PCR methodology closely follows the requirements of the relevantISO standards, while at the same time providing the necessary detail to enable the derivation of Type IIIEnvironmental Product Declarations (EPD).

Suggestions to improve the clarity of the PCR and to modify a number of technical issues were made andthese were implemented by BRE Global.


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Revision of BRE Global Methodology for Environmental Profiles

The BRE Global Environmental Profiles methodology will be revised by issue of revised editions oramendments. Details will be posted on our website at www.GreenBookLive.com . Specifically sections ofthe methodology most likely to be updated have been placed in appendices.

Technical or other changes which affect the requirements for the approval or certification of the product orservice will result in a new issue. Minor or administrative changes (e.g. corrections of spelling andtypographical errors, changes to address and copyright details, the addition of notes for clarification etc.)may be made as amendments.

The issue number will be given in decimal format with the integer part giving the issue number and thefractional part giving the number of amendments (e.g. Issue 3.2 indicates that the document is at Issue 3with 2 amendments).

Users of BRE Global methodology should ensure that they possess the latest issue and all amendments.
http://www.greenbooklive.com/http://www.greenbooklive.com/


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Foreword

Manufacturers of construction products, designers, users and owners of buildings and others active inthe building and construction sector are demanding information that will enable them to makedecisions which address environmental impacts of buildings and other construction works. Anincreasingly common solution is to create environmental product declarations .

Environmental product declarations are similar to the nutritional information found on the back of foodpackets. They list the impacts caused throughout the life of a particular product.

It is essential that there is uniformity in the means of expressing environmental product declarations.This includes having a consistent way of arriving at the declaration and providing the information. Theuser expects unbiased, accurate and verified information, which is consistent with the best currentpractice and understanding.

To help achieve this, work has been on-going at both national and international levels. According tothe International Standards of the ISO 14020:2002 series, environmental labels and declarations aredivided into three principal types:

Type I (ISO 14024:2001) label: a defined environmental standard with ecolabels awardedto those who pass

Type II (ISO 14021:2001) claims: self-declared claims (e.g. recyclable)

Type III (ISO 14025:2006) declaration: nutritional labelling style environmental productdeclarations within a prescribed formula

These documents are supported by a fourth document: ISO 14020:2002, Environmental labels anddeclarations General principles . Additionally, a further ISO Standard has been specifically developedto create appropriate rules for applying the ISO 14025:2006 standard to construction products:

ISO 21930:2007, Sustainability in building construction Environmental declaration ofconstruction products.

Type III environmental product declarations must be based on Life Cycle Assessment (LCA), an areawhich has been covered by the ISO standards:

ISO 14040:2006, Environmental management Life cycle assessment Principle andframework

ISO 14044:2006, Environmental management Life cycle assessment Requirements andguidelines

Environmental product declarations have a number of alternative names in common use. Theseinclude Ecoprofiles, Ecolabels, Environmental Declarations. In this document they are referred to asEnvironmental Profiles.

This document provides information about the Environmental Profiles methodology for constructionproducts (see section 3), a type III environmental labelling scheme for construction products andelements. The methodology has been prepared to be in conformity with the relevant ISO standards ISO 21930:2007, ISO 14025:2006, and standards relating to Life Cycle Assessment in general, ISO14040:2006 and 14044:2006.


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BRE Global first published the Environmental Profiles methodology, BRE Methodology forEnvironmental Profiles of construction materials, components and buildings in 1999, with fundingfrom the DETR and the involvement of over 20 trade associations and industry bodies. Followingdevelopments in LCA techniques and the work undertaken for the ISO Standards, BRE Global choseto update the methodology, a process which has involved extensive stakeholder consultation.

The purpose of this methodology is to describe the principles and framework for environmentaldeclarations of construction products, including consideration of the reference service life (see section3) of construction products over a buildings life cycle. This methodology forms the basis for the BREGlobal Environmental Profiles Scheme , a Type III environmental declaration programme whichenables manufacturers and trade associations to make Type III environmental declarations ofconstruction products as described in ISO 14025:2006.

The overall goal of the BRE Global Environmental Profiles Scheme is to encourage the demand for,and supply of, construction products that cause less stress on the environment, throughcommunication of verifiable and accurate information on environmental aspects of those construction

products, thereby stimulating the potential for market-driven continuous environmental improvement.

This document will be of interest to individual construction product manufacturers and constructionproduct trade associations wishing to prepare an Environmental Profile, and data users, includingdesigners and clients, who wish to have a detailed understand of the basis of the information they areusing.

There are two clear benefits to having a single, industry-agreed method that is applicable to all typesof building product:

1. The application of the Environmental Profiles methodology allows manufacturers and tradeassociations to publish data about their products on the basis of a level playing field, i.e. in a

way that is comparable and robust for competing product types.

2. Using data produced by this methodology will give confidence to designers and buildingclients who wish to ensure that they have taken full account of the life cycle environmentalimpacts of the construction products they are using, using the latest developments in life cycleassessment and that the data they are using has been produced such that competingproducts have been evaluated in a fair and independent manner.

For more information about the Environmental Profiles Scheme: www.greenbooklive.com

A diagram showing how the various elements of Environmental Profiling fit together and how it is usedin building assessment schemes is given in Figure 1.
http://www.greenbooklive.com/http://www.greenbooklive.com/


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Figure 1: The key elements of the Environmental Profiles Scheme and its relationship to BREEAM 1,the Code for Sustainable Homes 2 and EcoHomes. This methodology is aimed primarily at theassessment and certification of products and materials for construction that are not wholly coveredunder current recognised standards and codes.

This scheme is reviewed by the BRE Global Sustainability Board which is a stakeholder technicalboard operated by BRE Global.

The methodology shall be used in conjunction with BRE Global Scheme Document SD 028 3.

1 BREEAM Centre. BREEAM: BRE Environmental Assessment Method. www.breeam.org

2 Communities and Local Government (CLG). The Code for Sustainable Homes. Available fromwww.communities. go.uk/thecode or from www.planningportal.gov.uk 3 Scheme Document for Environmental Profiles Certification Scheme SD028. BRE Global Ltd.

*To receive a Green Guide to Specification rating

and be eligible for credits in BREEAM, Code forSustainable Homes and EcoHomes, data fromindividual manufacturers must be independentlycertified by BRE Global, or other licensedprovider, to the Environmental CertificationScheme.

Generic data about productsand processes the

manufacture uses but does notown or operate

Manufacturers data entered intoEnvironmental Profiles Data

Capture Form

Data processed according to therules set out in BRE

Methodology for EnvironmentalProfiles of construction products

Data published as anEnvironmental Profile (alsoknown as an Environmental

Product Declaration)*

Products can help contribute toa Green Guide to Specification A+ to E rating depending upon

specification build up

Materials Credits can beobtained for:

BREEAM Code for Sustainable

Homes EcoHomes

Scope of Environmental Profiles Scheme
http://www.breeam.org/http://www.communities.go.uk/thecodehttp://www.communities.go.uk/thecodehttp://www.planningportal.gov.uk/http://www.planningportal.gov.uk/http://www.communities.go.uk/thecodehttp://www.breeam.org/


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NOTE: Compliance with this BRE Global methodology does not of itself confer immunity from legalobligations. Users of the methodology should ensure that they possess the latest issue and allamendments.

NOTE: BRE Global welcomes comments of a technical or editorial nature and these should beaddressed to the Technical Director at [email protected] .

NOTE: BRE, BRE Global and LPCB are owned by the BRE Trust which is a registered charity. BREGlobal tests, assesses, certificates and lists products and services within the construction,sustainability and fire and security sectors. For further information on our services please contact BREGlobal, Watford, Herts. WD25 9XX or e-mail to en [email protected] .

NOTE: Listed products and services appear in the BRE Globals Green Book Live which may beviewed on our website: www.GreenBookLive.com .
mailto:[email protected]:[email protected]:[email protected]://www.greenbooklive.com/http://www.greenbooklive.com/mailto:[email protected]:[email protected]


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Environmental Profiles: a methodology for the environmentaldeclaration of construction products in the UK

1 Scope of this document

This is a technical document and has not been prepared for the lay reader. For a simpler explanationof the scheme, see the BRE Global website.

This document provides the principles and requirements of the methodology that underpins the BREGlobal Environmental Profiles Scheme, a scheme that produces Type III environmental productdeclarations for construction products. Under the conventions of this scheme, the declaration is knownas an Environmental Profile.

The document describes the general programme requirements and the product category rules (PCR)(see section 3) for the Environmental Profiles of construction products. This methodology is basedupon International Standard ISO 21930:2007 Sustainability in building construction Environmentaldeclaration of construction products . This International Standard contains specific requirements forconstruction products and complements International Standard ISO 14025:2006 Environmental labelsand declarations Type III environmental declarations Principles and procedures, ISO 14040:2006 Environmental management Life cycle assessment Principles and framework, and ISO14044:2006 Environmental management Life cycle assessment Requirements and guidelines.

NOTE: In ISO 21930:2007 Sustainability in building construction Environmental declaration ofconstruction products , EPD is an abbreviation used to represent both the single and plural full formdesignation of environmental product declaration(s), which is intended to be synonymous with thedesignation Type III environmental declaration. In the practice of developing EPD, programmes ortheir declarations are referred to by various names such as Eco-Leaf, eco-profile, environmentaldeclaration of products and environmental profile. This scheme uses the name Environmental Profile.

This document describes in detail the consistent approach to the identification and assessment of theimpacts of all construction products over their life cycle that is used in the Environmental ProfilesScheme, including:

Goal and scope,

Inventory data collection procedures,

Preferred data sources,

Consistent treatment of transport,

Calculation of emissions from fuel use,

Allocating impacts to products from multiple product lines,

Allocating impacts to products which are recycled,

Impact assessment procedures for classification, characterisation and normalisation,

Format for Environmental Profiles.


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2 Normative references

Document ISO 21930:2007, Sustainability in building construction Environmental declaration ofconstruction products contains provisions, which, through reference in this text, constitute provisionsof this methodology.

ISO 21930:2007 draws on other related International Standards. To provide an indication of the rangeof related Standards a list is provided here. The related standards include:

ISO 6707-1:2004, Building and civil engineering Vocabulary Part 1: General terms

ISO 14001:2004, Environmental management systems Specification with guidance for use

ISO 14020:2002, Environmental labels and declarations General principles

ISO 14021:2001, Environmental labels and declarations Self-declared environmental claims(Type II environmental labelling)

ISO 14024:2001, Environmental labels and declarations Type I environmental labelling Principles and procedures

ISO 14025:2006, Environmental labels and declarations Type III environmentaldeclarations Principles and procedures

ISO 14040:2006, Environmental management Life cycle assessment Principles andframework

ISO 14044:2006, Environmental management Life cycle assessment Requirements andguidelines

ISO/TR 14047:2003, Environmental management Life cycle impact assessment Examplesof application of ISO 14042

ISO 14050:2002, Environmental management Vocabulary ISO/DIS 15392, Buildings andconstructed assets Sustainability in building construction General Principles

ISO 15686-1:2000, Buildings and constructed assets Service life planning Part 1: Generalprinciples

ISO 15686-2:2001, Buildings and constructed assets Service life planning Part 2: Servicelife prediction methods

ISO/DIS 15686-8 Buildings and constructed assets Service life planning Part 8: Referenceservice life

ISO/TS 21929-1:2006, Buildings and constructed assets Sustainability in buildingconstruction Sustainability indicators Part 1 Framework for development of indicators forBuildings

ISO/TS 21931-1:2006, Buildings and constructed assets Sustainability in buildingconstruction Framework for Assessment of Environmental Performance of ConstructionWorks Part 1 Buildings


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ISO/CD 21932:2006, Buildings and constructed assets Sustainability in building construction Terminology


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3 Terms and Definitions

For the purposes of this methodology, the terms and definitions given in ISO 21930:2007 apply.

NOTE: Terms are not defined where they retain their normal dictionary definition. Where bold type isused within a definition, this indicates a cross reference to another term defined in this clause, and thenumber reference for the term is given in parentheses.

3.1 ancillary product / complementary product

building product (see section 3.2) that enables another building product to fulfil its purpose in theintended application, for example fasteners used to attach structural panels to framing members

3.2 building product

goods or services used during the life cycle of a building or other construction works

NOTE: In this methodology, the term product used alone relates not only to product systems but canalso include service systems. In either case, the declaration is presented in a manner that clearlyindicates whether the declaration applies to goods, or only to a part of the goods or packaging, or toan element of service. This is discussed in ISO 14025:2006, see section 7.2.2.

NOTE: The manufacturing or processing of goods used as a building product may take place at thefactory or on the construction site.

NOTE: The use of services can occur at any stage of the life cycle of the building or other constructionworks.

NOTE: It is possible to have an Environmental Profile (see section 3.17) for a material, a buildingproduct, a component, an assembly and/or a building element. The Environmental Profiles of acomponent, assembly or building element can incorporate the results of the Environmental Profiles ofall the assembled materials and construction products. This is described in section 5.4 Modularity inISO 14025:2006.

NOTE: Adapted from the definition of product in ISO 6707-1:2004 and ISO 14021:2001.

NOTE: Whereas ISO use building product, in this methodology the term construction product isused. There is no difference in meaning intended between the two terms as defined above and thechoice is based on the more common usage of construction product in the UK.

3.3 characterisation factor

factor derived from a characterisation model which is applied to convert an assigned life cycleinventory analysis (LCI) result to the common unit of the category indicator

3.4 declared unit

quantity of a building product (see section 3.2) for use as a reference unit in an EnvironmentalProfile (see section 3.17), based on LCA, for the expression of environmental information needed ininformation modules (see section 3.7). For example mass (kg), volume (m)

NOTE: The declared unit will only be used where the function and the reference scenario for the wholelife cycle, on the building level, cannot be stated.


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3.5 functional unit

quantified performance of a product system for a building product (see section 3.2) for use as areference unit in an Environmental Profile (see section 3.17) based on LCA

3.6 gate

point at which the building product (see section 3.2) or material leaves the factory before it becomesan input into another manufacturing process or before it goes to the distributor, a factory or buildingsite

3.7 information module

compilation of data to be used as a basis for a Type III environmental declaration (see section3.17), covering a unit process or a combination of unit processes that are part of the life cycle of aproduct

3.8 non-renewable resource

resource that exists in a fixed amount that cannot be replenished on a human time scale

3.9 PCR review

process whereby a third party (see section 3.15) panel verifies the product category rules (seesection 3.11)

3.10 product category

group of construction products (see section 3.2) that can fulfill equivalent functions

3.11 product category rules (PCR)

set of specific rules, requirements and guidelines for developing Type III environmental declarations (see section 3.16) for one or more product categories (see section 3.10). The BRE Globalmethodology applies to the product category construction products.

NOTE: The term PCR has been replaced by methodology in this document. The two terms may beused interchangeably.

3.12 reference service life

service life of a building product (see section 3.2) that is known or to be expected under a particular

set, i.e., a reference set, of in-use conditions and which may form the basis of estimating the servicelife under other in-use conditions

NOTE: The reference service life is applied in the functional unit (see section 3.5) / declared unit (see section 3.4)

3.13 renewable resource

resource that is grown, naturally replenished or cleansed on a human time scale, e.g. trees in forests,grasses in grasslands and fertile soil.

NOTE: A renewable resource is capable of being exhausted, but may last indefinitely with proper

stewardship.


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3.14 sequestration (of carbon)

the removal and long-term storage of carbon dioxide from the atmosphere through the use of naturalcarbon sinks, primarily in forests in the form of increasing plant biomass

3.15 third party

person or body that is recognised as being independent of the parties involved, as concerns theissues in question

NOTE: "Parties involved" are usually supplier ("first party") and purchaser ("second party") interests.

3.16 Tonne.km (t.km)

unit of distance accounting for the mass being transported; expression of Mass and Distance.

NOTE: 100t transported 1km (100t.km) is equivalent to 1t transported 100km (100t.km)

3.17 Type III environmental declaration / environmental product declaration (EPD) /Environmental Profiles

environmental declaration providing quantified environmental data using predetermined parametersand, where relevant, additional environmental information

NOTE: The predetermined parameters are based on the ISO 14040 series of standards, which ismade up of ISO 14040:2006 and ISO 14044:2006.

NOTE: The additional environmental information may be quantitative or qualitative.

3.18 waste

This method does not seek to define waste. ISO 21930:2007 defines waste as substances or objectswhich the holder intends or is required to dispose of. This definition is included here as a usefuldescription.

NOTE: The ISO definition is taken from the Basel Convention on the Control of Trans-boundaryMovements of Hazardous Wastes and Their Disposal (22 March 1989) but is not confined tohazardous waste


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4 Symbols, Abbreviations and Acronyms

4.1 Symbols and Abbreviations

Energy mega joule MJ

Energy kilowatt hour kWh

Mass tonne (metric ton) t

Mass kilogram kg

Mass gram g

Surface square metres m 2

Volume cubic metres m 3

4.2 Acronyms

BRE Building Research Establishment

BREEAM BRE Environmental Assessment Methodology

CFC chloro-fluoro-carbons

CHP combined heat and power

CML University of Leiden: in the Netherlands

CSH Code for Sustainable Homes

EPD environmental product declaration

EU European Union

GWP global warming potential

HCFC hydrogenated chloro-fluoro-carbons

ISO international standards organisation

LCA life cycle assessment

LCI life cycle inventory

LCIA life cycle impact assessment

LEC levy exemption certificates

ODP ozone depletion potential

PCR product category rules


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REGO renewable energy guarantees of origin certificates

ROC renewable obligation certificates

VOC volatile organic compounds


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5 General aspects of the Environmental Profiles Scheme

5.1 Goal

The overall goal of Environmental Profiles is to encourage the demand for, and supply of, constructionproducts that cause less stress on the environment, through communication of verifiable and accurateinformation on environmental aspects of those construction products, thereby stimulating the potentialfor market-driven continuous environmental improvement. This is part of the BREEAM family of tools,created to enable more sustainable construction.

This document provides information about the methodology for preparing Environmental Profiles forconstruction products.

This common methodology used to create Environmental Profiles allows for comparisons to be madebetween different types of construction products, based on units of equivalent functional performanceat a building level, created according to the standards required by 2006 Approved BuildingRegulations for England and Wales.

5.2 Scope

This methodology provides the rules necessary for the declaration of environmental information ofconstruction products in the form of Environmental Profiles. Environmental Profiles are used for theassessment of the environmental performance of the fabric, structure, finishes and fittings of buildings.

The methodology identifies all the significant environmental aspects associated with the life cycle ofconstruction products, according to the guidance on identifying significant environmental aspects inISO 14001.

Only environmental impacts and aspects are considered. The social and economic aspects ofsustainability are excluded.

The working environment (during product production or construction) is not included.

The impacts in use/operation (e.g. heat loss avoided by use of insulation) are excluded, exceptmaintenance and replacement of the products over their life. These aspects of materials performanceare considered in the building performance criteria within the BREEAM standards and in the Code forSustainable Homes. They are also considered in envest2 4, which brings the data from EnvironmentalProfiles together at a whole building level.

The rules stating what is included and what is excluded when creating an Environmental Profile areset out in section 6.4.

NOTE: The impacts in use/operation depend on a number of factors outside the scope of anEnvironmental Profile for construction products, including the size, form and function of the buildingand occupant behaviour.

Environmental information in an Environmental Profile covering all life cycle stages ( cradle to grave )comprises data from the following four life cycle stages:

4 BRE. Envest. Available from www.bre.co.uk/envest
http://www.bre.co.uk/envesthttp://www.bre.co.uk/envest


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product stage (raw material supply, transport, manufacturing of products, and all upstreamprocesses from cradle to gate);

construction process stage (transport to the building site and building installation/construction);

use stage (maintenance, repair and replacement, refurbishment);

end of life stage (recycling and disposal; all including transport).

From distinguishing these different levels, it is clear that there are two types of Environmental Profiles:for products and for building elements . These have distinct properties, as shown in Table 1.

Providing the data for these is the responsibility of different parties and the table distinguishes this.

This document can therefore be used in two ways: to identify the basic requirements of amanufacturer who wishes to prepare an Environmental Profile and for interested parties to identifyhow the data is treated to create an Environmental Profile once it has been provided to BRE Global

Limited, the programme operator.

Table 1: The three types of Environmental Profile

Profiletype

Life Cycle stages included Study units Use forComparison

Responsible party

Cradleto

gate

Production stage (raw material supply, rawmaterial transport, manufacturing of products,and all upstream processes from cradle togate).

Informationmodule: pertonne

Shall not beused forcomparison

In-factory (gate togate) data collectedby manufacturer

Pre-factory data forraw materialsprovided by BREGlobal

Cradleto site

As for cradle to gate

AND

Construction process stage (transport ofproduct to the building site and wastage frombuilding installation/construction only)including transport and disposal of waste.

Informationmodule: persquare metreinstalledelement

Shall not beused forcomparison

As above

AND

Constructionprocess dataprovided by BREGlobal

Cradle

tograve

As for cradle to site

AND

Use stage: repair, replacement, maintenanceand refurbishment including transport of anymaterials and disposal of waste over thestudy period.

Demolition: is expected to occur any time ator after the end of the study period and isincluded within this Environmental Profile. Itincludes transport and disposal of waste.

Functional

unit: persquare metreinstalledelement overa 60-yearstudy periodin the building

Can be used

for comparisonif thefunctional unitis equivalent

As above

AND

Life-time dataprovided by BREGlobal


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NOTE: It is possible to have an Environmental Profile for a material, for a product and for acomponent, an assembly and/or a building element. The Environmental Profiles of a component,assembly or building element can incorporate the results of the Environmental Profiles of all theassembled materials and construction products. This is described in section 5.4 Modularity in ISO14025:2006.

NOTE: Transport of people for any form of labour at any stage in the life cycle is not included, e.g.construction or maintenance.

The terminology of cradle to cradle assessment is often applied to LCA models. The EnvironmentalProfiles methodology does not use this description and BRE Global prefer to use the term cradle tograve assessment. This is in recognition of the fact that Environmental Profiles are most commonlycommunicated using a defined study period of 60-years (see Appendix 1). This means they have aclear time horizon and point of conclusion. The reality of this however, is that many of the materialLCA models could also be accurately described as cradle to cradle assessments. Cradle to cradleassessment occurs when materials at the end of their life are usefully reused or recycled into future

scenarios. This most commonly occurs with metals, but other materials such as plastic, timber andaggregate and concrete also benefit from this practice. In conclusion, although the EnvironmentalProfiles methodology uses the description of cradle to grave to characterise its life cycle models, thereality is that many of the models can also be accurately described as cradle to cradle in scope.

5.3 Objectives

The purpose of an Environmental Profile for construction products is

1. To provide a measurable and verifiable input for the assessment of the environmentalperformance of buildings.

2. For interested parties to compare the environmental impacts of different construction productsas they are used within a building, based on units of equivalent functionality.

3. To provide a means of collecting relevant data for the preparation of tools for comparing theenvironmental impacts of construction products, including the Green Guide to Specification 5 and the envest2 software for the environmental assessment of whole buildings. These areused to give credits for the use of materials with a lower than average environmental impact inthe BREEAM family of environmental assessment tools for buildings and the Code forSustainable Homes.

5.4 Audience

Environmental Profiles of construction products are intended to provide information for planning andassessing buildings and are intended mainly for business-to-business communication. This does notpreclude their use for business to consumer purposes, where third party verification has beenobtained.

The users of this methodology are information users, who may include trade associations,manufacturers in the manufacturing chain, designers, developers, architects, contractors, facilitymanagers and their clients.

5 BRE Global. The Green Guide to Specification Online. www.thegreenguide.org.uk
http://www.thegreenguide.org.uk/http://www.thegreenguide.org.uk/


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RBS

Waste and Resources Action Programme (WRAP)

Willmott Dixon

A number of additional interested parties had membership of the project steering group to ensureconstruction industry representation:

John Bowdidge, Independent LCA expert

Construction Products Association*

National Building Specification (NBS)

RIBA

RICSNOTE: *The Construction Products Association was a member of this group as representatives of theconstruction products industry but made no financial contribution to the project. This status wasestablished to ensure no conflict of interest and to reflect the substantial contribution of theconstruction products sector in meeting the cost of processing new Environmental Profiles LCA data.None of the additional parties were financial sponsors of the project.

5.6 .1 .2 Group 2 Cons t ruct ion Products As socia t ion: manufacturers advisory g roup

This was a special working group convened by the Construction Products Association and was calledthe manufacturers advisory group. Other trade associations not affiliated to the Construction Products

Association and industry members of the BRE Global Environmental Profiles Certification Schemewere also consulted throughout the development process.

5.6.1.3 Group 3 LCA exp ert adviso ry p anel

The following experts in LCA and building materials were consulted on different aspects during thedevelopment of this methodology:

Wayne Trusty, Athena Sustainable Materials Institute, Canada.

John Bowdidge, independent LCA expert, UK.

Jean Luc Chevalier, Head of the Environment and Durability Division, Materials DepartmentCSTB (Centre Scientifique et Technique du Btiment), France.

Sverre Fossdal, Senior Researcher, Norwegian Building Research Institute.

Rolf Frischknecht, ESU-services, Switzerland.

Tarja Hkkinen, Chief Research Scientist, VTT Building and Transport, Finland.

5.6.2 Peer review panel

The following experts in LCA and buildings have undertaken a peer review of this methodology:

Wayne Trusty, Athena Sustainable Materials Institute, Canada. (Chair).


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John Bowdidge, Independent LCA expert, UK.

Eva Schmincke, Five Winds Consultancy, Germany.

5.7 Responsibility for the Environmental Profiles

Data for an Environmental Profile are in two forms: the raw data (Life Cycle Inventory LCI) and thedata processed into environmental impacts assessed by Characterising and Normalising the data(Section 7) so that it is known as Life Cycle Assessment (LCA) data.

Two types of Environmental Profile exist:

with generic data provided by trade associations and groups of manufacturers.

with proprietary data provided by manufacturers and certified by BRE Global.

The responsibility for the data is different according to the type of data.

The manufacturer, group of manufacturers or Trade Association who have provided the data for thebuilding product is the owner of and takes responsibility for the LCI data, in both proprietary andgeneric Environmental Profiles.

BRE Global is the owner of and takes responsibility for the LCA data in Proprietary, CertifiedEnvironmental Profiles and with generic data.

BRE Global has an agreement with the manufacturers and trade associations it works with to use theLCA data that it prepares on their behalf within tools such as the Green Guide to Specification and topublish Environmental Profiles with their permission.

5.8 Product Category At its highest level, the scheme is applied to a single product category: construction materials. Thisdocument sets out the Product Category Rules (PCR) for all construction materials. Where exceptionsapply for particular groups, these are clearly stated.

NOTE: The methodology can be applied to non-building applications such as infrastructure. Anappropriate functional unit will be created.

5.9 Comparability of Environmental Profiles of construction products

Comparison of construction products using Environmental Profiles shall only be carried out at the

building level, using a functional unit of an installed element within a scenario. The EnvironmentalProfile Per installed element over 60-year study period in the building (cradle to grave) provides this.This document describes the rules and requirements for how the 60-year scenario is created.Comparability of construction products using Environmental Profiles is in accordance with therequirements for comparability as described in ISO 14025:2006, Clause 5.6.

Environmental Profiles for the equivalent functional unit prepared using the methodology set out in thisdocument are deemed to be comparable.

5.10 Data confidentiality

Data from manufacturers is stored securely. Access is limited to staff working as part of the

Environmental Profiles Scheme. Data confidentiality as a restriction on publication is described inSection 8.


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5.11 Keeping the methodology up to date

This is the second edition of the Environmental Profiles methodology. The first edition was publishedin 1999. An addendum to the first edition was published in 2000.

Developments in the LCI data sources and standards and Building Regulations for England and Waleswill be reviewed by BRE Global at a minimum interval of three years. BRE Global as the programmeoperator will form an opinion on significance of the changes identified, with contribution from the PCRReview Panel. The BRE Global Sustainability Board will make the final decision. The intention is tomaintain the PCR according to latest best practice, within the financial constraints of operating thescheme such that it is commercially viable and accessible to new and existing manufacturerparticipants.


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6 Methodological framework

6.1 General

The methodology is designed to be consistent, scientifically robust and to ensure that burdens andimpacts are comprehensively accounted for without any double counting or undercounting.

The methodology is also designed to be consistent for all stages of the life cycle across all materialclasses i.e. the winning of raw materials and fuels, energy conversion, chemical processes,manufacture, fabrication, transport, waste from installation (see section 6.4), use (i.e. repair andmaintenance, refurbishment), demolition, reuse or recycling and disposal.

6.2 Data collection

Data is collected by manufacturers using a standard questionnaire (see Appendix 6).

Inventory data is collected for the following items:

Inputs:

o Materials

o Transport

o Process Fuel

o Heat

o Water

Outputs:

o Emissions to air

o Discharge to water

o Emissions to land

o Products, co-products, by-products and wastes

Manufacturers provide a process tree, including any major transportation stages with a clearly markedsystem boundary to indicate included and excluded processes. The resulting inventory is checked forbalance in mass (including taking account of evaporation of water). The total mass flowing into thesystem boundary must be accounted for with an equivalent mass flow out of the system boundary.Figure 2 illustrates the generic components of a process tree. Energy consumption is checked forappropriateness compared to known systems.


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98% by mass of inputs must be included therefore a maximum of 20 kg of inputs per tonne ofproduct output (2% of 1 tonne) can be ignored, and then, if they have:

significant effects or energy use in their extraction, their use or disposal, or

are highly toxic, or

are classed as hazardous waste

they must be included.

Mass balance checks ensure the inputs stated are sufficient to produce all the outputs, includingwaste arising. The methodology adjusts input inventories proportionally to 100% where it is notpossible to quantify internal process waste.

NOTE: The application of these rules is by BRE Global. Manufacturers discuss their process with BREGlobal prior to completing the questionnaire to determine how the cut-off rule applies to them.

A manufacturing plant often has offices attached, and the power, water and waste associated withthese premises are included in the Environmental Profile. If the head office is situated on the samesite as a manufacturing plant, it is not included in the assessment.

6.4.2 Boundary rule: Cut-off criteria for environmental impacts

Thirteen environmental impacts are reported. These are the impact categories provided in section 7.1.No cut-off criteria are provided for environmental impacts resulting from the included material flows; allare included within the assessment and all environmental impacts are reported.

6.4.3 Boundary rule: Capital equipment and infrastructure

The contribution of capital equipment and infrastructure (e.g. a factory building) is not normallyconsidered in LCA and is not included here. Maintenance of equipment is also not included in the LCAexcept for frequently consumed items which are included in the inventory if they meet the data 2% cut-off rule in Section 6.4.1 or are deemed to have a significant impact.

NOTE: The application of the 2% and significance rule is determined by BRE Global. Manufacturersdiscuss their process with BRE Global prior to completing the questionnaire to determine how thisapplies to the maintenance of their equipment.

6.4.4 Boundary rule: Energy use in factory and factory support offices

All energy used in factories and factory support offices is included. Head offices and sales offices etc.are excluded.

6.4.5 Boundary rule: Construction impacts

Construction process impacts are not accounted for except for waste. Data sets are not widelyavailable and the impact is considered to be small and unfeasible to allocate to products.

In particular circumstances where there are considered to be especially great impacts from theconstruction process, the energy impacts will also be included. This is important for the considerationand comparison of offsite and onsite manufactured systems.

6.4.6 Boundary rule: Site wastage

Site wastage during the construction and refurbishment process is included.


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Wastage rates are collated through the consideration of data from a number of sources. A costinghandbook, Laxtons 6, includes wastage rates for the most popular specifications. This is used as adefault source to collate wastage rates for construction materials within particular contexts, in terms ofuse within the building (e.g. timber as studwork, within window frames and as floorboards), whether

the project is new build or refurbishment, and size of project. The rates are checked throughconsultation with manufacturers or trade associations for appropriateness and tailored models arecreated where evidence is available for particular construction practices.

To create the Environmental Profile for a specification, the appropriate context for each material usedis selected as part of the specification process and the relevant wastage rate for first installation andany subsequent replacements are calculated.

6.4.7 Boundary rule: Lifetime use: maintenance

Maintenance is considered where the environmental impacts are significant (as per section 6.4.1) andmay vary depending on the use of the product within the building. Typical maintenance for a product

within a given specification will be considered. Transportation impacts for personnel and plant are notincluded in maintenance models.

The quantity and transport of any significant materials used (e.g. in painting and varnishing) over thelifetime of a product will be included.

For flooring a model of cleaning impacts over the lifetime is included. This takes account of water,materials and energy used but not transport of cleaning staff to the site.

6.4.8 Boundary rule: Lifetime use: contribution to lifetime - energy use in a building

This boundary rule applies to construction element Environmental Profiles only and does not apply toper tonne Environmental Profiles.

All the element specifications have been designed to achieve the requirement set out in section 6.3.This allows the designer to consider the overall impact from quantities of different materials required toproduce different building solutions without having to consider differences in energy consumptionresulting from different thermal resistance values. In general, comparison between elements with thesame functional unit can ignore lifetime energy use within the assessment. However, care should betaken where aspects such as thermal mass may have implications on energy consumption in thebuilding.

Where a building element, for example a modular construction system, is normally built to a better Uvalue than the functional units defined in Appendix 1, section A1.2.3, BRE Global will adapt it to meet

the U value defined in the functional unit. This ensures it is not penalised for the use of more materialsto achieve a higher U value.

6.4.9 Boundary rule: Demolition

The impact of the demolition process is not included. Data sets are not widely available and the impactis considered to be small and difficult to allocate to specific materials. However the impact of disposalof material arising from demolition is considered based on section 6.4.10.

6 VB Johnson & Partners (Eds). Laxtons Building Price Book, 2006: Major and small works. Oxford, Butterworth-Heinemann, 2005


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6.4.10 Boundary rule: Disposal

The boundary of the LCA includes the impacts of disposal of all materials. Models for the amounts forconstruction materials estimated to go to landfill, incineration, recycling and reuse are described insection 6.8.1.

The models for landfill and incineration are described in section 6.8.2.

The impacts of recycling and reuse are allocated in accordance to the procedures in section 6.9.2 andsection 6.9.3.

6.5 Data quality requirements

The data quality requirements of the Environmental Profiles methodology are fully explained in Appendix 2. This provides information about the quality of data provided by industry and the upstreamdata sets used to create the Environmental Profiles.

The ecoinvent 2000 database is the default data source used for quantifying the impact of inventorydata. If manufacturers are able to provide more specific, quality data about a product or processingthey are using, this will be used as a preference, in accordance with the data quality requirements setout in Appendix 2.

6.6 Energy

6.6.1 Electricity models

Detailed LCA models for electricity production for national production across Europe have beendeveloped on behalf of the Swiss Government, as part of the ecoinvent database.

These models:

are based on generation in 2000

are based on national models of energy mix for electricity production

cover all resource use and emissions to air, water and land, for all stages of the electricitysystem, from resource extraction, fuel refining, storage, generation and distribution ofelectricity

include imports and exports of power between countries

exclude impacts from infrastructure which includes the building of power stations, wind farms,dams, and supply network including pylons and cables) over the lifespan of the powerproduction with the exception of renewable energy infrastructure, which is considered to havea higher proportion of energy embodied in the infrastructure compared to energy generatedover the life time of the infrastructure compared to conventional energy sources

include different LCA models for High Voltage (direct supply to some major industries),Medium Voltage (most industry) and Low Voltage Supply (domestic and offices). Distributionlosses increase as voltage lowers.

For non-European countries where electricity models are not available in ecoinvent, national electricitymodels can be created based on the national energy mix for electricity generation using ecoinvent

models for electricity generation from specific fuels.

The most appropriate voltage model will be used.


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6.6.1.1 Company specific electricity model

Where a company has invested in the construction of a specific power plant from which it takes themajority or all of the supply, then the use of a specific LCA model for that power plant will beconsidered based on ecoinvent data, but adapted where relevant for the specific installation, forexample in terms of emissions or infrastructure (where significant as per section 6.4.3). Theenvironmental impact associated with the manufacture of the equipment and its anticipated lifespan isaccounted for in the model.

6.6.2 Renewable electricity

For electricity purchased from green tariffs for renewable or other generation, then the profile will bebased on the specific mix using ecoinvent data.

Green tariffs within the UK will need to demonstrate that Renewable Energy Guarantees of Origincertificates (REGOs) are held, and that Levy Exemption Certificates (LECs) and Renewable Obligation Certificates (ROCs) have been retired for the electricity supplied 7. Overseas green tariffs will need todemonstrate a similar level of renewable sourcing and additionality. Any other green tariffs will becalculated with the standard national electricity mix. 8

See also waste-derived fuels (see section 6.6.4) and biofuels (see section 6.6.5).

6.6.2.1 Onsite generation of electricity

If a manufacturer has invested in the generation of electricity on site, then the appropriate electricitymodel will be used for that supply which is used by the manufacturer based on ecoinvent data oractual data if available. This applies equally to renewable or conventional energy. The environmentalimpact associated with the manufacture of the equipment and its anticipated lifespan is accounted forin the model. The manufacturer will need to provide evidence that LECs and ROCs for the onsitesupply have not been sold on to any other parties, in which case the standard national electricity mixwill be used.

6.6.3 Fuels

LCA data for fuels is derived from the ecoinvent database. This data:

is the latest available data source for fuels (2000)

includes all upstream extraction, production and distribution impacts

excludes infrastructure (e.g. building of oil wells and refineries) and supply network (e.g.building and operation of pipelines) over the lifespan of fuel production

Profiles are available for the production of different fuels (including natural gas, coal, coke, light andheavy oil, wood) and for their performance in boilers or furnaces, according to their different sizes (e.g.>100 kW) and different technologies (e.g. modulating/condensing boilers).

7 This means that the carbon dioxide savings are claimed and not available to be passed on to further processes.

8 Note that green tariffs are treated differently in this methodology compared to BREEAM and the Code forSustainable Homes. This method is able to demonstrate that the green energy is consumed. The other schemesare dealing with future scenarios.


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Figure 3: How the impact of waste fuels is allocated to manufacturers if they pay for the fuel or pay for the deliveryof the fuel.

The impact of transport of waste fuels will be carried by the waste producer if they pay for the disposalof the fuel or the delivery of the fuel. Figure 4 provides a diagram to illustrate this process.

InputsProcess X Product

X

Waste (tobe used

as fuel orinput)

Emissions

Process Y

Product Y

Emissions

As Process Y buys the waste fromProcess X to use as a fuel or input,it receives a proportion of theimpact of Process X, based on the% of income that Process Xderives from selling the waste.

Inputs

10% Process X impact

passed to Product Y.

As Process X sells its waste to Process Y, deriving 10% of itsincome, it can allocate 10% of its impact to Product Y and 90% toProduct X. The Waste from Process X is considered as a co-product of Process X

90%

Process Ximpact toProduct X

100% ProcessY impact toProduct Y


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Figure 4: How the impact of waste fuels is allocated if the waste producer pays for the disposal of the fuel or thedelivery of the fuel.

6.6.5 Biofuels

As plants grow they absorb CO 2 from the atmosphere and convert the carbon in it to plant matter suchas cellulose. This process is known as sequestration .

Fuels derived from agriculture or forestry (e.g. wood or bio-diesel) or from organic wastes such aspaper or food waste, have sequestered the carbon they contain within the time period of the last 100years. Any emissions of CO 2 from burning these fuels (known as biogenic emissions) are thereforereturning it to the atmosphere without causing any net increase in CO 2 over this timescale. Bothsequestered (removed) CO 2 and biogenic (emitted) CO 2 flows are included within the Environmental

InputsProcess X Product

X

Waste (tobe usedas fuel or

input)

Emissions

Process Y

Product Y

Emissions

As Process Y receives 10% of itsincome by taking waste fromProcess X and using as a fuel or aninput, 10% of the impacts ofproducing Product Y (and disposingof waste) are passed back toProcess X. Waste Disposal forProcess X is considered as a co-product of Process Y.

Inputs

10% Process Yimpact passed backto Product X

As Process X pays to dispose ofits waste, it receives some of theimpact of Process Y which takesit.

100%

Process Ximpact toProduct X

90%Process Yimpact toProduct Y


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6.7 Transport

6.7.1 Transport to factory gate

For transport of materials to the factory, data is obtained from

the manufacturers for the distance travelled,

mode of transport (e.g. sea, rail, and road),

vehicle or ship type and

average loads or number of deliveries and return load. An average default return load isassumed for the return journey. If the return load is empty, the return journey is considered tobe equal to the outward journey. Part loads are accounted for. No adjustment is made forlighter loads. Shipping in container ships is considered as a single route only.

If distances are not provided, then BRE Global will use default data provided by the Department forTransport from the continuing Survey of Roads Goods Transport 9. For shipping, standardiseddistances by sea are calculated using the Maritime Chain 10 . For road distances, a web-based tool isused 11 .

6.7.2 Transport from factory to site

Manufacturers are asked to provide data on the typical methods of transport of the product to theconstruction site. This includes distance travelled, vehicle type and average load and return load ifany. In the absence of this information, BRE Global uses the default data described in section 6.7.1.

Wherever possible, specific data is used, to take account of variables in weight and volume betweenproducts. A separate questionnaire is provided to record this as part of the data collection process(see Appendix 6).

6.7.3 Calculating inventory data for transport

6.7.3.1 Road transp ort exclud ing m unic ipal waste col lect io n, t ractor and trai ler and van < 3.5tonnes

For road transport, the overall distance and tonnes.km (t.km) travelled by each vehicle type iscalculated based on the average number of deliveries. Fuel consumption is calculated based on directfuel consumption figures obtained from UK DfT Road Freight Statistics 2005 12 and the overalldistance travelled.

Infrastructure for road transport including road building and maintenance, lorry and tyre maintenanceand replacement is not included within the Environmental Profiles.

9 Typical load and haul data for 2005 calculated for common commodities used in construction and productmanufacture from an extract from the Continuing Survey of Road Goods Transport provided to BRE by theDepartment for Transport in a personal communication (21.11.2006)

10 www.maritimechain.com

11 e.g. www.multimap.com 12 htt p://www.dft.gov.uk/162259/162469/221412/221522/222944/coll_roadfreightstatistics2005in/rfs05comp.pdf
http://www.maritimechain.com/http://www.multimap.com/http://www.dft.gov.uk/162259/162469/221412/221522/222944/coll_roadfreightstatistics2005in/rfs05comp.pdfhttp://www.dft.gov.uk/162259/162469/221412/221522/222944/coll_roadfreightstatistics2005in/rfs05comp.pdfhttp://www.dft.gov.uk/162259/162469/221412/221522/222944/coll_roadfreightstatistics2005in/rfs05comp.pdfhttp://www.multimap.com/http://www.maritimechain.com/


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6.7.3.2 Rail , water and air t ranspo rt and mun icipal waste co l lect ion, t ractor and trai ler and van< 3.5 tonn es

For rail and ship transport, the overall t.km travelled by each transport type is calculated. This unit isan expression of distance and tonnes moved.

Ecoinvent models for the energy and impact associated with transport are then used based on thetotal t.km travelled by each mode of transport.

Rail transport is assumed to be a mix of electric and diesel, based on a European average.

Infrastructure for rail, water and air transport is not included within the Environmental Profiles.

6.8 Disposal

6.8.1 Disposal routes for construction materials

Disposal route models have been produced by BRE Global in consultation with Trade Associations.These are based on the most likely scenario for construction materials at disposal, consisting of thepercentage of material sent to each disposal route (landfill, incineration, recycling and reuse) usingpractical evidence gathered during site audits and industry surveys. Where relevant, they are alsospecific to construction waste, refurbishment waste and demolition waste. These models are used tocalculate the relevant impacts of the disposal route using the ecoinvent data.

A standard waste model is applied unless manufacturers provide evidence that an alternative scenariois more typical. The standard models are checked with manufacturers for appropriateness and tailoredmodels are created where evidence is available for particular disposal practices.

The waste model for biological materials such as wool or wood is considered with regard to the carbon

cycle and this is dealt with in section 6.12.

6.8.2 Waste models for waste treatment and disposal

The ecoinvent database has a number of waste treatment models for incineration, landfill and wastesorting which are detailed and include a number of models for specific wastes and technologies. Fromthese models, the following items are included in an Environmental Profile: transport to wastetreatment and any emissions arising from the waste treatment. Infrastructure and the impacts fromcapping and lining layers are excluded. Whilst waste treatment continues to have impacts forthousands of years, only impacts for the first 100 years from disposal are included in these models.

Infrastructure associated with waste treatment and disposal is not included within the Environmental

Profiles.

6.8.3 Waste water treatment models

The ecoinvent database has produced a generic LCA model for waste water treatment which allowsthe content of waste water to be evaluated in terms of its impact. This model allows different sizes ofwaste water treatment facility (from 800 230,000 per capita facilities) to be evaluated. A base loadfor sewerage is assessed for all plants and additional materials are accounted for on a case by casebasis. The model is adapted for on-site water treatment.


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6.9 Allocation

6.9.1 Allocation of material flows

A standardised procedure is used to calculate how different materials produced by the same plant

should share the environmental burdens resulting from the manufacturing process. This is calledallocation. The type of process requiring allocation is illustrated in Figure 6.

Figure 6: A process which will require allocation for the apportioning of impacts to multiple productsand wastes

A number of approaches can be taken according to ISO standards. BRE Global has developed amethod within this context. This complies with ISO requirements but the BRE Global methodologydoes exclude some approaches due to the requirements of the goal and scope for consistency acrossall product types.

The materials, energy flows and associated emissions are allocated to the different productsaccording to the following order of preference:

1. Avoid allocation, by division of a single process into sub-processes: Figure 7

2. Allocate by physical property (excluding stoichiometry): Figure 8

3. Allocate by product value (economic allocation): Figure 9

Processes requiring allocation:multiple products/wastes

Product 1

Product 3

Product 2

Product 4

Waste 5

Process


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Allocation by product value is illustrated in Figure 9 where two or more outputs come from a singleprocess, and sub-division and physical allocation are not appropriate, then burdens are allocatedaccording to the proportion of product revenue earned from the different outputs. This is known aseconomic allocation. Any output from such a process will attract burdens on the basis of the relativeincome it generates compared to the overall income generated by the process. Any outputs which donot generate income for the manufacturer are not allocated any impacts from the manufacturingprocess.

The price that is used to make the allocation is the average three-year market price of the relevantmaterials. This makes allowance for fluctuating global markets. Manufacturers are also able to provideproportions of output by value if price data is commercially sensitive.

For sequential processes, the system boundary is expanded to account for them collectively.

In cases where the data cannot be separated for the two processes, the system boundary can beexpanded to encompass both processes, and allocation by product stream value will be used toallocate burdens between the products.

EXAMPLE Steel manufacturing produces steel and slag. Slag is used in concrete manufacture anddisplaces cement. If slag is 2/tonne and steel is 150/tonne, the impact of making cement can bededucted from the impact of making steel for a proportion of the process equivalent to the relativeprice of slag to steel.

There are a number of processes where the physical properties are used to allocate particular impactsbetween products and co-products and value is used for the other impacts. These are for carbonsequestration (see section 6.12) and for minerals extraction.

EXAMPLE 1 A saw-mill produces sawn timber, saw dust and bark. The amount of carbonsequestered within each is that which is physically sequestered within the product. The overall amountof sequestered carbon entering the system is that within the timber entering the saw-mill. Once thesequestered carbon for the products and co-products has been calculated, any remaining sequesteredcarbon (for example within wood waste used as fuel) is followed through the system. Where the fuel isburnt, the resulting greenhouse gas emissions are allocated to the sawn timber and sawdust by value.

All remaining impacts from the saw-mill process are allocated to the products and co-products byvalue.

EXAMPLE 2 A quarry produces cut stone. In situations where large amounts of smaller pieces ofstone and other associated minerals are generated as part of the quarrying process, this is likely to be

sold as aggregate. Using value-based allocation, we would simply allocate the minerals depletionimpact according to the relative value of the cut stone and the aggregate. If this aggregate would beliable for the UK Aggregates Levy, then it will be considered to have a mineral resource depletionimpact (see Appendix 4) of 1 tonne of minerals resource depletion per tonne of material extracted.This minerals extraction would then be deducted from the total amount of minerals extraction for thequarry, to give a minerals extraction impact which would be allocated by value to the products and co-products. Any other impacts (e.g. fuel use, minerals extraction from overburden) are also allocated tothe products and co-products on the basis of value.


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Figure 9: Third allocation choice by value for multiple products and wastes.

6.9.2 Allocation, waste and recycling

The outputs may include co-products , by-products and reusable and recyclable wastes all of which

might find application in further processes, together with wastes which must be disposed of andpollution which must be carried by the environment. The same allocation hierarchy as per section6.9.1 is used for by-products and reusable and recyclable wastes as for co-products, but because sub-division and physical allocation are rarely appropriate for these outputs, economic allocation as persection 6.9.1 is normally used.

Particulates collected from gas streams and de-watered sludge and solids from treated effluents, mineoverburden waste from mining and extraction operations and furnace slag, ash, bark and sawdust areall considered as outputs. Some materials produced during a manufacturing process may be:

recycled or reused in the process

sold

taken away free of charge by another company for recycling

sent to waste disposal at a cost to the producer or

recycled by another company at a cost to the producer.

Other outputs from a process may include services (e.g. waste disposal) or energy (e.g. electricity),some of which may generate revenue for the process.

A precise definition of waste is not provided in this methodology. All outputs from a process (a

product, waste or service) where sub-division or physical allocation cannot be used are treated usingthe economic allocation procedure as per section 6.9.1.

Multiple products/wastes:Third Choice: Allocation by value

Product 1

Waste 3

Product 2

Product 4

Waste 5

Process

Mass * /tonne

Mass * /tonne

Mass * /tonne

Mass * /tonne

Mass * /tonne

Product Impact:Mass * /tonne * ImpactTotal Value


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Economic allocation means that each output from the process will attract burdens on the basis of therelative income it generates compared to the overall income generated by the process. Any outputwhich is given away or which the manufacturer has to pay to dispose of will not attract any burdensfrom the manufacturing process. Outputs which the manufacturer pays to dispose will attract burdensfrom the disposal/treatment process back into the manufacturing system. These scenarios are furtherillustrated in Figure 10.

Figure 10: The two models of end of life recycling which illustrate the influence of value on thecontribution that recycling makes to the final impact of a product.

6.9.3 Allocation for post-consumer materials which are recycled and reused

Many processes manufacture a primary product which after use is likely to be recycled or reused. Therecycling may be into the same product as the original or into one with a lower-grade application. Theproblem faced is how to ensure that the recycled or reused product carries an appropriate amount ofthe environmental impact from the original process into the new product.

End of Life Recycling I

Product 1Process A Process B Recycling Product 2

Use

Impact from Process A or B will carry forward if there is value from recycling

Does any impact come from making product 1 carry forward?

If Product 1 has no value at end of use NOIf Product 1 has any value at end of use YES

End of Life Recycling II

Product 1Process A Process B Recycling Product 2

Use

Impact allocated to recycling = End of life value * Impact to Base PointBase Value

BASE Point: After which processing has no further benefit to recyclingExamples:

Rolling sheet metal isnt of value for recycling: Metal Ingot/Slab = base pointGlass to glass bottles isnt of value for recycling: Glass = base point

End of life Value: massarising * /tonne

Base Value:1 tonne * /tonne


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The thinking behind the Environmental Profiles procedure follows that for allocation to co-products andis therefore based on economic value. This is one of the allocation approaches for recyclingrecommended in ISO 14044:2006.

The underlying concept is that when manufacturing a primary product, some of the primarymanufacturing impact will be transferred forward to any future recycling on the basis of the relativevalues of the primary product and the material arising in the waste stream for recycling or reuse.Therefore any post-consumer recycled input will incur a proportion of primary impact calculatedaccording to its value relative to that of the primary manufacturing process. Scrap material withoutvalue will carry no burdens forward.

EXAMPLE When a steel frame building is demolished, the steel sections within the building have avalue as a resource for recycling. A proportion of the impact of their primary manufacture is allocatedforward to this recycling, based on the relative values of the primary production stream and the wastearising.

Allocation to post-consumer recycling is undertaken from the point in primary manufacture at whichfurther processing is no longer useful in terms of recycling. This is called the "base point", and thematerial the "base material". Only the impacts up to the base point are allocated to the recycledproduct. Any subsequent manufacturing beyond the base point will be totally allocated to the primaryproduct.

EXAMPLES:

a glass bottle recycled into another glass object the base point is just before the glass (basematerial) is made into bottles

aluminium foil the base point is the aluminium ingot (base material) before it goes to rolling

steel section the base point is the manufacture of steel slab (base material) before sectionmanufacture

Therefore, in the example above of the glass bottle, the impact of bottle manufacture is only carried bythe first use of the bottle, but some of the impact of glass manufacture will be allocated to post-consumer recycling. For the aluminium foil, some of impact of aluminium ingot production is allocatedforward to recycled aluminium, but the foil manufacturing process will only be allocated to the use ofthe foil.

6.9 .3 .1 Al locat ion to pos t -consu mer recycl ing

The allocation to recycling is based on the cost of the base material at the base point and this iscompared to the cost of the material arising for recycling to give the proportion of impact which istransferred to any recycled product.

However, this allocation for recycling can only be undertaken when recycling actually happens. Thismeans a further calculation for the proportion of material recycled must also be used in the equation,based on the current recycling rate.

In other words, of products manufactured today, the proportion assumed to be recycled in the future isthe percentage based on current recycling rates. Recycling rates for demolition waste have beencollected by BRE Global and consulted on with industry in the development of this methodology.

EXAMPLE Continuing the example from above of aluminium foil, the amount of impact allocated torecycled aluminium will be based on the relative value of aluminium ingot being produced and thecorresponding value of aluminium which would be expected to arise for recycling.


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For one tonne of ingot, the three-year average is approximately 1250, the product yield from 1 tonneof ingot is 0.988 tonnes, and the estimated scrap arising is 90% of this figure, 0.9 tonnes, with a valueof approximately 750/tonne.

The amount of impact allocated forward to future recycling is therefore:

%54)12501()7509.0( =

Any post-consumer recycled input into a process will carry impact calculated in this way, and this iscalculated in the same way for pre-consumer waste as post-consumer recycling. For closed loop pre-consumer recycling, the per tonne impacts carried forward to recycling will match the per tonne impactbrought with the recycled input, though there may be additional impacts for the recycled input basedon any secondary processing.

For the above example, any recycled aluminium includes the burdens carried forward from primary

manufacture. However as recycled aluminium has a similar value to primary aluminium, and is aslikely to be recycled, then a similar proportion of impact will be carried forward to its own next use.

Where a product with recycled input is recycled again at the end of life, then the impact from primarymanufacturing will again transfer forward to this future recycling. Reprocessing and re-melting of scrapinto ingot etc. is of no value to any future recycling process, so the base point is the value of thescrap, compared to the value of the scrap after use, so there is no change in value, therefore only thelosses through recycling rate and yield need to be accounted for and this impact from primaryproduction will remain with any recycled input.

6.9.3.2 Alloc at ion to reuse

Allocation to reuse follows a similar principle to that above, but with a different base point. In thisrespect, allocation to reuse is undertaken from the point of final manufacture at which furtherprocessing is no longer useful in terms of reuse.

For example for a steel section which is reused, the manufacture of both steel slab and steel section isuseful to the reused product, and therefore the base point is after steel section manufacture.

Allocation is based on the cost of the final product, and the amount of final product manufactured.This is compared to the cost of the product arising for reuse and the amount of product arising forreuse based on current reuse rates (again sourced by BRE Global). Any additional impacts ofmanufacturing that are not useful for reuse (e.g. labelling or packaging) are allocated to the primaryproduct (in the scenarios common within construction, these impacts are not generally significant asper section 6.4.1).

6.10 Units to be used for inputs and outputs

energy: mega joules, MJ; or kilowatt hours, kWh

mass: tonne, t; or kilogram, kg; or gram, g

6.11 Imports

The inputs and outputs attributed to imports of materials and products are, wherever possible, basedupon analyses appropriate to the country of origin and include the energy of transportation. Where

data for the country of origin are not available, the input and output data are based upon the closestdomestically produced product with an addition made for the transportation from the country of origin.


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7 Life Cycle Impact Assessment

7.1 Characterisation factors

Where available, the characterisation factors applied have been developed by the University of Leiden(CML) in the Netherlands. Where there are gaps in areas of environmental impact important tobuilding materials, characterisation factors have been developed by BRE Global.

CML prepares its characterisation factors by basing them on work undertaken by the most expertgroups or researchers in the respective area, e.g. their climate change characterisation factor is basedon the findings of the Intergovernmental Panel on Climate Change.

In 2000, CML published an updated characterisation methodology. The CML indicators use a midpointapproach which has a direct link between the inventory and endpoint. Further information on the CMLmethod can be found on their website 14 .

Characterisation categories have been created for five additional areas of environmental impact whichare significant for construction products and which are not considered by CML. The areas are FossilFuel Depletion, Waste Disposal, Nuclear Waste, Minerals Extraction and Water Extraction.

The Environmental Profiles methodology uses and reports the following environmental impactcategories and reference characterisation units:

Climate change: kg CO 2 eq. (100 yr)

Stratospheric ozone depletion: kg CFC-11 eq.

Eutrophication: kg phosphate (PO 4) eq.

Acidification: kg sulfur dioxide (SO 2) eq.

Photochemical ozone creation - (summer smog): kg ethene (C 2H4) eq.

Human toxicity: kg 1,4 dichlorobenzene (1,4-DB) eq.

Ecotoxicity to water: kg 1,4 dichlorobenzene (1,4-DB)eq.

Ecotoxicity to land: kg 1,4 dichlorobenzene (1,4-DB) eq.

Fossil fuel depletion: tonnes of oil equivalent (toe)

14 Guine et al, Life cycle assessment: an operational guide to the ISO standards. CML, Leiden University 2000.This can be downloaded in 4 parts from

Part 1: LCA in perspective: http://www.leidenuniv.nl/cml/ssp/projects/lca2/part1.pdf

Part 2a: Guide: htt p://www.leidenuniv.nl/cml/ssp/projects/lca2/part2a.pdf

Part 2b: Operational Appendix: htt p://www.leidenuniv.nl/cml/ssp/projects/lca2/part2b.pdf

Part 3: Scientific Background: htt p://www.leidenuniv.nl/cml/ssp/projects/lca2/part3.pdf

Part 2b provides more detail on the exact baseline methodologies and characterisation factors for the chosencategory indicators
http://www.leidenuniv.nl/cml/ssp/projects/lca2/part1.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part1.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part2a.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part2a.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part2a.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part2b.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part2b.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part2b.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part3.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part3.pdfhttp://www.leidenuniv.nl/cml/ssp/projects/lca2/part3.pdfhttp://www.leidenuniv.nl/cml/ssp/pro

methodology for environmental profiles 2008 sd6050

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